A recent study published in the journal Neuropsychopharmacology provides evidence that a single dose of the psychedelic drug LSD can improve motor learning the next day and reduce perceived stress up to a week later. The research also reveals subtle, lingering changes in how the brain processes auditory information and controls muscle movements. These findings suggest that LSD may temporarily enhance certain types of learning and psychological flexibility, opening the door for potential therapeutic applications in physical rehabilitation.
Lysergic acid diethylamide, commonly known as LSD, is a powerful psychedelic compound known for altering perception and mood. In recent years, this substance has emerged as a potential treatment for mental health conditions like depression and anxiety. Traditional psychiatric treatments often require daily medication, making a single-dose treatment highly appealing. A single dose of a psychedelic tends to produce therapeutic effects that can persist for months.
This extended timeline suggests that the drug might induce lasting physical or functional changes in the brain. Animal models indicate that LSD and similar drugs might trigger these changes by promoting neuroplasticity. Neuroplasticity refers to the brain’s ability to reorganize its neural networks and grow new connections.
Preclinical studies hint that psychedelics might create a temporary window where learning becomes much more efficient. This window of enhanced learning could apply to simple conditioning as well as complex social behaviors. However, evidence regarding these lingering effects in humans remains scarce. Past research has mostly focused on the immediate experience of the drug rather than what happens in the days following the trip.
Abigail Calder, a postdoctoral researcher at the University of Fribourg in Switzerland, noticed this disparity in the scientific literature. “We knew of the theory that psychedelics stimulate neuroplasticity, and neuroplasticity is closely connected to learning,” Calder said.
“As we planned the study there was beginning to be a lot of research on psychedelics and neuroplasticity, but there was almost nothing on learning,” Calder explained. “It seemed like time to begin filling in that gap.”
The authors of the current paper designed an experiment to track human brain activity and behavior after the initial effects of LSD faded. They specifically wanted to investigate motor learning, which involves the brain’s ability to pick up and consolidate new physical skills. Motor learning holds significant clinical relevance for physical rehabilitation and recovering from brain injuries.
By measuring sensory processing, motor system excitability, and psychological functioning, the team aimed to map out how a single dose of LSD influences the nervous system over a one-week period. The experiment involved a randomized, double-blind crossover trial with 45 healthy participants. The volunteers were aged between 21 and 55, and data from 43 participants were analyzed.
Each person attended two separate dosing sessions at least four weeks apart. In one session, they received a full 100-microgram dose of LSD, and in the other, they received an inactive placebo. Participants were told the placebo might be a very low dose of LSD to help manage their expectations.
During the sessions, the scientific team used electroencephalography, widely known as EEG, to record electrical brain activity. Through electrodes placed on the scalp, they measured how the brain responded to a series of auditory tones. They specifically focused on two types of brain waves, known as the N1 and P2 components.
The N1 wave reflects early sensory processing, while the P2 wave tends to track attentional focus and novelty detection. The researchers also attempted to measure brain plasticity using a technique called sensory tetanization. This method involves playing very rapid tones to see if the brain’s electrical response strengthens over time.
In addition to brain waves, the team applied transcranial magnetic stimulation to measure the excitability of the brain’s motor system. This technique uses a magnetic coil placed against the head to send safe, brief pulses into the motor cortex. To test for neuroplasticity, they paired these magnetic pulses with a mild, painless electrical shock to a nerve in the participant’s wrist.
These paired pulses cause a measurable muscle twitch in the participant’s right thumb. The scientists recorded the size and speed of these twitches to gauge how responsive the motor system was under the drug’s influence. They repeated this process across several time points to track changes in muscle responsiveness over a full week.
To check for chemical markers of brain growth, the team took blood samples to measure brain-derived neurotrophic factor. This specific protein helps support the survival of existing neurons and encourages the growth of new synapses. Blood was drawn before drug intake, as well as eight hours, one day, and one week later.
The researchers checked both blood plasma and blood serum to ensure they did not miss any subtle chemical changes circulating in the body. One day after taking the drug, participants completed a sequence typing task to test their motor learning. They used their non-dominant hand to type a nine-digit number sequence on a keyboard as quickly and accurately as possible.
The task measured “online” learning during ten active practice rounds. It also measured “offline” learning, which refers to the brain’s ability to consolidate and improve a skill after a period of rest. The participants rested for ten minutes and then for eighty minutes before being tested again. Finally, participants completed psychological questionnaires to assess their perceived stress levels and cognitive flexibility one week after the initial dosing session.
The scientists found that LSD produced measurable changes in both behavior and brain activity. On the motor learning task, participants showed significantly greater improvements in typing speed one day after taking LSD compared to the placebo condition.
“We saw that a single, moderately strong dose of LSD (100 micrograms) improved motor learning the next day, on a typing task,” Calder told PsyPost. “LSD was associated with improved learning consolidation, which is the phase of learning that takes place during rest after practicing a motor skill.”
This improvement specifically occurred during the “offline” resting period rather than during the active practice rounds. Participants improved their typing speed by roughly 33 percent more after the eighty-minute rest period when they had taken LSD. The drug did not affect their typing accuracy, indicating that they were not simply sacrificing precision for speed. “This suggests that psychedelics like LSD might temporarily (though quite modestly!) improve the ability to learn new motor movements,” Calder noted.
The EEG recordings showed that LSD acutely reduced the size of the N1 and P2 brain waves on the day the drug was given. This reduction suggests a temporary disruption in early auditory processing and a shift in how the brain allocates attention to external sounds. The reduction in the P2 brain wave persisted the next day and showed signs of lingering up to one week later.
However, the rapid-tone sensory tetanization procedure failed to produce the expected signs of brain plasticity in either group. Magnetic stimulation of the motor cortex revealed that brain-to-muscle signals became faster and larger on the day participants took LSD. The next day, the size of these muscle responses decreased compared to the placebo condition.
Calder found these immediate physical reactions particularly intriguing. “While people were on LSD (about 8 hours after dosing), we saw larger, faster muscle movements in response to TMS stimulation of the motor cortex,” Calder said.
“It especially surprised me that their movements were any faster than usual,” Calder added. “We still don’t know why that was, or even if it’s useful knowledge. But it was a novel finding.”
The blood tests did not show any changes in brain-derived neurotrophic factor levels at any point during the study. This lack of change might occur because blood levels of this protein do not always accurately reflect protein levels inside the brain. On the psychological questionnaires, participants reported lower levels of perceived stress one week after the LSD session.
They also scored higher on a subscale measuring their ability to generate alternative solutions to difficult situations, which represents a key component of cognitive flexibility. During the active drug experience, side effects were common but generally mild and transient, matching typical psychedelic experiences.
Interpreting these findings requires noting a few constraints in the experimental design. The researchers intended to use rapid audio tones and magnetic pulses to directly measure long-term changes in neural plasticity. These specific measurement techniques failed to produce the expected baseline effects even when participants took the placebo.
This lack of baseline response made it impossible to confirm if the motor learning improvements were definitively driven by enhanced neuroplasticity. The motor learning gains observed the day after taking LSD might be explained by lingering effects on motivation or attention. If participants felt more engaged or aroused the day after their psychedelic experience, they might have simply performed better on the typing task.
“We aren’t sure how reliable the effect on motor learning is, how long it lasts, or under what exact circumstances it arises,” Calder cautioned. “We also don’t know if it generalizes to other types of learning, and we actually can’t even say whether it’s directly related to neuroplasticity.”
To prevent people from jumping to incorrect conclusions, Calder provided a practical warning about these early results. “So hold off on taking LSD before trying to study or start skiing lessons,” Calder said.
The scientists also noted that LSD often causes mild muscle tension or shaking during the peak drug experience. Because they did not measure resting muscle tension before applying the magnetic brain pulses, they cannot be sure if the faster muscle twitches were due to changes in the brain or simply tense muscles in the hand. Additionally, participants correctly guessed when they received the full dose of LSD due to its strong psychoactive effects.
This lack of successful blinding means that participants’ positive expectations about psychedelics could have influenced their lower stress scores. Future research projects will need to address these variables by including objective, task-based measurements of stress and motivation. Tracking participants over a longer period would also clarify if the improvements in motor learning and psychological flexibility persist over time.
“First and foremost, it’s important to replicate these findings in other samples to make sure they’re reliable,” Calder said regarding future studies. “I’m also excited to investigate whether LSD’s alleged effect on motor learning generalizes to other types of learning (like learning new emotional patterns in psychotherapy), how long learning effects last (days? weeks?), and whether other psychedelics also stimulate learning ability.”
Calder also emphasized a broader need within this scientific field to improve methodology. “We also need to get better at reliably and non-invasively measuring neuroplasticity in humans,” Calder said.
The study, “Acute and post-acute neurobehavioral responses to lysergic acid diethylamide in healthy subjects: a randomized controlled study,” was authored by Abigail E. Calder, Vincent J. Diehl, Morten P. Lietz, Parsa Yousefi, Nicole Friedli, Fabio Coviello, Antonin Rouaud, Kristian Beichmann, Anne Eckert, and Gregor Hasler.